Rosetta's Amazing 10-Year Space Journey

More than a decade ago, the European Space Agency launched an orbiter named Rosetta, bound on a circuitous voyage to comet 67P/Churyumov-Gerasimenko. In the years since, Rosetta has been drawn in and flung along by multiple gravity assist maneuvers, visiting the Earth three times and making observations of the Moon, Mars, and several asteroids and comets. In January of this year, after 31 months of hibernation, Rosetta re-awoke, nearing comet 67P. Recently, it approached to within 100 km of the comet, entering orbit and preparing to send a lander to the surface. The lander, named Philae, will be deployed in November, securing itself to the comet with harpoons and drills to prevent it from bouncing away in the weak gravity. The lander and orbiter are then scheduled to ride along, escorting the comet on its upcoming close approach to the Sun next August, all the while sending imagery and data home to be combined with Earth-based observations. Gathered here are some snapshots of Rosetta's incredible trip so far.

Comet 67P/Churyumov-Gerasimenko imaged by the OSIRIS narrow-angle camera aboard the European Space Agency's Rosetta spacecraft on August 3, 2014. The photograph was taken from a distance of 177 miles (285 kilometers), with a resolution of 17 feet (5.3 meters) per pixel. Comet 67P measures approximately 4 km (2.5 mi) along its longest axis.#

This view of Mars (brightest point) and of the Milky Way was taken by the OSRIS camera on board the Rosetta orbiter on December 3, 2006, during the last series of instrument check-outs. In this image Mars is heavily overexposed and therefore surrounded by a halo of scattered light.#

Rosetta's self-portrait above Mars. On February 25, 2007, Rosetta passed just 250 km from the surface of Mars. Rosetta's Philae lander took this image 4 minutes before closest approach, at a distance of 1,000 km. It captures one of Rosetta's 14 m-long solar wings, set against the northern hemisphere of Mars, where details in the Mawrth Vallis region can be seen. Representative color has been added to the surface of Mars in this image.#

This image of the Moon was taken with by Rosetta's OSIRIS Narrow Angle Camera (NAC) on November 13, 2007, about nine hours after Rosetta's closest approach to Earth during one of its gravity assist maneuvers.#

The OSIRIS camera on board the Rosetta spacecraft observed Earth during a swing-by in November of 2007. A sun-illuminated crescent can be seen around Antarctica in this image, a color composite combining images obtained at various wavelengths.#

Anticyclone over the South Pacific. During its third and final flyby of Earth on November 13, 2009, Rosetta imaged this anticyclone over the South Pacific. The closest approach was at exactly 07:45:40 GMT, as Rosetta passed just south of the Indonesian island of Java, at an altitude of 2,481 km, traveling at 48,024 km/h (29,841 mph).#

In this image provided by the European Space Agency the lights of North American cities can be seen. The photograph was taken by Rosetta's OSIRIS Imaging System's Narrow-Angle Camera at 11:44 p.m. EST on November 12, 2009 just before Rosetta's closest approach to Earth. Some of the cities are clearly visible. Others like New York are covered by clouds, making the light diffuse.#

Asteroid Lutetia at closest approach. On its way to a 2014 rendezvous with comet 67P/Churyumov-Gerasimenko, Rosetta flew past asteroid Lutetia on Saturday, July 10, 2010. The instruments aboard Rosetta recorded the first close-up image of the biggest asteroid so far visited by a spacecraft. Rosetta made measurements to derive the mass of the object, understand the properties of the asteroid's surface crust, record the solar wind in the vicinity and look for evidence of an atmosphere. The spacecraft passed the asteroid at a minimum distance of 3,160 kilometers (1,950 miles) and at a velocity of 15 kilometers (9 miles) per second, completing the flyby in just a minute.#

After 31 months of hibernation, a wakeup signal is received from Rosetta on January 29, 2014 at the European Space Operations Center in Darmstadt, Germany. At center, Andrea Accomazzo, ESA Rosetta Spacecraft Operations Manager, celebrates with other team members.#

On approach. This on July 14, 2014 animated sequence combines 36 interpolated images of comet 67P/Churyumov-Gerasimenko, each separated by 20 minutes, showing the rotation of the complex body. The images were obtained from a distance of approximately 7,500 miles (12,000 kilometers).#

Close-up detail focusing on a smooth region on the base of the 'body' section of comet 67P/Churyumov-Gerasimenko, taken by OSIRIS on August 6, 2014. The image clearly shows a range of features, including boulders, craters and steep cliffs. The image was taken from a distance of 80 miles (130 kilometers) and the image resolution is 8 feet (2.4 meters) per pixel.#

Jagged cliffs and prominent boulders are visible in this image taken by OSIRIS from a distance of 62 kilometers from comet 67P/Churyumov-Gerasimenko on September 5, 2014. The left part of the image shows a side view of the comet's "body", while the right is the back of its "head".#

Comet 67P/Churyumov-Gerasimenko, observed by the Very Large Telescope. Astronomers on Earth have been busy following comet 67P with ground-based telescopes. As Rosetta is deep inside the "atmosphere" coma, the only way to view the whole comet is to stand back and observe it from Earth. This image was recorded on August 11, 2014 using one of the 8 m-diameter telescopes of the European Southern Observatory's Very Large Telescope in Chile. Although faint, the comet is clearly active, revealing a dusty coma extending at least 19,000 km from the nucleus.#

Comet 67P/Churyumov-Gerasimenko, imaged by OSIRIS August 7, 2014, from a distance of 104 km. While the comet's head (in the top half of the image) is covered with parallel linear features, the neck displays scattered boulders on a smooth underground. In comparison, the comet's body (lower half of the image) seems to have much more jagged features.#

Philae's primary landing site will target Site J, the center of which is indicated by the cross in this OSIRIS narrow-angle image. Site J is located on the head of the comet. Site J offers the minimum risk to the lander in comparison to the other candidate sites, and is also scientifically interesting, with signs of activity nearby. At Site J, the majority of slopes are less than 30 degrees relative to the local vertical, reducing the chances of Philae toppling over during touchdown. Site J also appears to have relatively few boulders and receives sufficient daily illumination to recharge Philae and continue science operations on the surface beyond the initial battery-powered phase.#

Using the CIVA camera on Rosetta's Philae lander, the spacecraft snapped a "selfie" at comet 67P/Churyumov-Gerasimenko. The image was taken on September 7, 2014, from a distance of about 50 km from the comet, and captures the side of the Rosetta spacecraft and one of Rosetta's 14 m-long solar wings, with 67P/C-G in the background. Two images with different exposure times were combined to bring out the faint details in this very high contrast situation.#